Larger sizes have two drill holes for secure sew-on embellishments or necklace, earring and bracelet links. Crystal beads have foil backing for added sparkle. The "P" in the color name stands for "Protective Layer," which is a lacquer system applied over the crystal luminous green effect. The lacquer is designed to protect the effects from scratches, fingerprints and other damage and also helps to prevent moisture that can lead to corrosion (example: from perspiration).